New Twiddle

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  actions: {
    destroyRecord(model) {
      model.get('children').then( (children) => {
      	//children.invoke('deleteRecord');
        //children.forEach( (child) => {
        //  child.deleteRecord()
        //});
        children.toArray().invoke('deleteRecord');
      });
    }
  }
});

models.child.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  parent: belongsTo('parent')
});

models.parent.js

import Model from "ember-data/model";
import attr from "ember-data/attr";
import { belongsTo, hasMany } from "ember-data/relationships";

export default Model.extend({
  children: hasMany('child')
});

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  model() {
    let children = [];
    for(var i=0; i<5; i++) {
      children.push(this.store.createRecord('child'));
    }
    return this.store.createRecord('parent', {children: children});
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{model.children.length}}
<br>
<button {{action 'destroyRecord' model}}>OMG Destroy parent and children</button>
<br>

twiddle.json

{
  "version": "0.10.6",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.9.0",
    "ember-data": "canary",
    "ember-template-compiler": "2.9.0",
    "ember-testing": "2.9.0"
  },
  "addons": {}
}